Chronocoulometric interrogations of oxidase‐based enzyme electrodes for enhanced selectivity

Abstract

AbstractClassical oxidase‐based enzyme electrodes rely on the amperometric determination of H2O2. Such electrodes are vulnerable to electroactive interferants found in biological solutions. Some interferants may be oxidized at anodic potentials, necessitating the use of permselective barrier membranes. Two generic chronocoulometric approaches to the interrogation of oxidase‐based enzyme electrodes have been developed. Both the chronocoulometric interrogation of H2O2 and the chronocoulometric interrogation of the reduction of O2 (formed from the anodic oxidation of H2O2) have allowed new correlations to be made with 0 to 20 mM glucose concentrations. Furthermore, the inter rogation of O2 has allowed a glucose sensor to be constructed that is virtually free from the effects of electroactive interferants.